Last week a new movie called "Railways" opened in Tokyo. It's about a driver on a small rural electric train line who retires after 40 years and is sort of a sequel to a film with the exact same title released in 2010. That movie centered on a Tokyo executive who loses his job and decides to pursue his boyhood dream of becoming a train driver. Both films appeal to male boomers, but the nostalgic interest central to the newer movie's promotion has to do less with its subject than with its 59-year-old star.

Tomokazu Miura has been an actor since he was 18, and a surprisingly successful one considering his narrow range and lack of on-screen charisma. His show-business longevity is based on one ancillary attribute: He is married to Momoe Yamaguchi, the most popular idol singer of the 1970s, who retired at the age of 21 in 1980 to marry Miura. Since then she has never made a comeback, nor has she appeared in public in any capacity except as the object of paparazzi. These days her only connection to the larger world is her husband, who over the years has never talked about her or their marriage in any meaningful way, even though he seems to understand that his career was more or less based on the fact that he was Mr. Momoe Yamaguchi.

In the past month, however, while doing promotion for "Railways," Miura has agreed to talk about his private life. In fact, the movie's release coincides with the publication of a memoir, "Aisho," which Miura wrote at the urging of the publisher that backed the film. The actor has said that initially he didn't want to write a book about himself, but filming ended around the time of the earthquake last March and he decided he could help victims by donating all proceeds from sales of the book to relief efforts. It's been one of Amazon Japan's Top 20 best-sellers since it was published in November.